X-brace construction for collapsible invalids&#39; wheel chairs



N 1952 H. A. EVEREST ETAL ,3

x BRACE CONSTRUCTION FOR COLLAPSIBLE INVALIDS WHEEL CHAIRS Filed Dec. 26, 1951 FIG. 2.

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HARRY C. JENA/l/V65,

' INVENTORS.

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Patented Nov. 18, 1952 Herbert A. Evrstand Harry .0. Jennings,- Lii's Angeles,= Calif.

"Afipliatiofi-Dedemlier 26, 1951,.seria1rie. 2%.314

This inventieri "reiatesto impreveme temmvanes wheel; chairs; and may beregarded I as an im"'fov'ementqveij thedisclosure made in our i' Paten-t-No. 2;1-81-,420, iss'ued November 28,-

ianetqry of th presem invention, collapsibl invalids wheel chairs have heretofore been designe consistingof two opposed side framessupported on drive andcaster wheels and which are cgllapsibly connected together by means of aux-breed Theg members of the X-brace usu-- ally. extendfrom the seat bar ofone side frame ower rung on the opposed side frame; and thnlBI}brS'-jpf the X- brace cross each beneath thesat'the'yare connected to each oth'r'by means of 'a pivot pm. If the wheel chair is rolling on afiunevensurface and the side frames are rigidlyconne'cted to each other situatifiiisaf-is 'Whieifi 'dia'gb'fl'lly apprised ground wheels are supported on high spots of the surface '3" claims; (01. rah-i463 and the other diagonally opposed ground wheels frame may at all times remain in firm contact with the surface and the ground wheels on the opposing side frame may do likewise. In our Prior United States Letters Patent No. 2,181,420 this warping movement of one side frame relative to the other is provided by a long pivot bolt extending through the members of the X-brace which permits the members of the X-brace to approach each other or recede from each other as is required in enabling one side frame to warp relative to the other.

An object of the present invention is to provide an improved connection between the members ofthe X-brace which will enable this warping movement of one side frame relatively to the other to be readily accomplished.

With the foregoing and other objects in view, which will be made manifest in the following detailed description and specifically pointed out in the appended claims, reference is had to the .2. I accompanyingdrawing for-ani'llustrativ'e embodiment ofthe invention,--whe reiri:- J r Figure l is a view in side-elevation .or-ewne'ei chair embodying the present invention Figr 2 is a sectional view taken substantiall y upon the line 22upon-Fig-.1;-and z Fig. 3- is a sectional view on an enlarged scale taken substantially upon the line 3-3 upon Fig.2.

Referring to the accompanying drawing'wherein similar reference characters designate similar parts throughout; the; improved wheel chair con;- sists of two opposed side frames l0 and H which are counterparts of each othen and usually formed of metal tubing- These side frames i'nelude longitudinallyextending' seat bars I! and I3 and-longitudinally extending rungs I4 and-1'5 The-side frames are each equipped with a drive wheel I 6 and acaster wheel" I I. Eachside frame may also include additional structure 'as' illus: trated but which formsno part of the pres t invention and is consequently not" described i-fita The two side frames are connect'ed to each other for collapsing movement by an X-brace,

e the members of Which are indicated at'l'ii and-1 9.

Each X-brace member is pivotally connected 'such asby aknuckle or the equivalent to the seat bar of one side frame. Each X-brace member is also pivotally connected at its lower end to the rung of the opposed side frame. In the usual construction the seat bars 13 are connected by a flexible seat 20 and are vertically slidable at their ends on the front and rear legs of their respective side frames. This construction enables the two side frames to be pushed towards each other and enables the chair to be collapsed by the X- brace sliding the seat bars upwardly on the legs of their respective side frames.

The members of the X-brace are pivotally connected to each other where they cross each other, and the present invention concerns the type of pivotal connection between the members of the X-brace that will not only permit the X-brace members to pivot relatively to each other but also enable the warping movement of one side frame relatively to the other. To this end, each X-brace member at about its center has a bushing rigidly secured therein. This bushing may be pressed or brazed in place and the two bushings are indicated in Fig. 3 by the reference characters 2| and 22. One bushing is disposed transversely of the X-brace member I8 and the other bushing is disposed transversely of the X-brace member [9. A pivot bolt 23 extends through both bushings and is slightly longer than the combined thicknesses of the two X-brace members. Each bushing is internally tapered from its outer end inwardly so that at the adjacent ends of the bushings the fit of the bushings around the pivot bolt 23 is fairly close. However, outwardly of this close fitting portion there is a steadily increasing clearance as indicated at 24 and 25. While a coil compression spring may be positioned about the bolt 23 to urge the X-brace members towards each other somewhat as shown in our prior Patent No. 2,181,420, such compression spring can be omitted in the present construction and is consequently illustrated as having been omitted.

The clearance space shown between the X-brace members due to the length of the bolt is ordinarily adequate to permit the X-brace members to approach each other or to recede from each other as the frames warp relatively to each other. The warping movement of one frame relatively to the other, however, produces some inclination of one of the X-brace members with respect to its opponent and the tapering clearance at 24 and 25 in the bushings permits of such inclination, it being understood that the bolt 23 merely assumes the required inclined position from the horizontal position shown Within the clearance spaces. The relatively close fit between the inner ends of the bushings and the pivot bolt tends to retain a smooth working pivot action between the members of the X-brace at all times.

The above-described construction is advantageous in that it permits of the use of a comparatively short pivot bolt and while the pivot bolt must be somewhat longer than the combined thickness of the X-brace members, it need not be excessively long. The ability of the pivot bolt to tilt Within the bushings as far as is'permitted by the tapered clearances 24 and 25 enables warping of one frame of the chair relatively to the other all of the distance necessary in usual conditions under which the wheel chair is used.

Various changes may be made in the details of construction without departing from the spirit and scope of the invention as defined by the appended claims.

We claim:

1. A collapsible invalids wheel chair comprising two opposed side frames, an X-brace connecting the side frames, a pivot bolt extending through the members of the X-brace where they cross each other, and bushings in the X-brace members through which the pivot bolt extends, said bushings having a relatively close fit about the pivot bolt at their inner ends but having a relatively loose fit around the pivot bolt adjacent their outer ends.

2. A collapsible invalids wheel chair comprising two opposed side frames, an X-brace connecting the side frames, a pivot bolt extending through the members of the X-brace where they cross each other, and bushings in the X-brace members through which the pivot bolt extends,

said bushings having a relatively close fit about I the pivot bolt at their inner ends and having a tapered interior providing a constantly increasing clearance toward their outer'ends.

3. A collapsible invalids wheel chair comprising two opposed side frames, an X-braceconnecting the side frames, a pivot bolt extending through the members of the X-brace where they cross each other, and bushings in the X-brace members through which the pivot bolt extends, said bushings having a relatively close fit about the pivot bolt at their inner ends and having a tapered interior providing a constantly increasing clearance toward their outer ends, the length of the pivot bolt being slightly greater than the combined thicknesses of the X-brace membersl HERBERT A. EVEREST. HARRY C. JENNINGS.

REFERENCES CITED The following references are of record in the file of this patent: 

